Yes, I agree, in fact it could indeed be
'her mother'.
I wonder who took the photo? Maybe that was who wrote the note here....
It
might have been 'Nina's' second husband - who, it seems from a census record, was deaf and dumb, and was a 44yo widower. He would have been around then (unlesss she'd bumped him off!)
Seeing as my Mum was in her full Girl Guide uniform in the photo, I might try and contact the Girl Guide Association and see if they hold any archives.... She may have a badge (among the many) on her blouse that shows which troop she belonged to. THAT might give a hint as to where the 'Grove' was....